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gillman's avatar
gillman
Explorer
Aug 01, 2017

Champion 3500/4000 Generator won't run AC unit?

Need some advice. Many years back, we had a travel trailer and I purchased one of these low-cost gensets. It was a little loud but sure ran the 13,500 BTU AC unit and other little items in the camper just fine. I used it extensively after Hurricane Ike for power to the house as well. I finally just wore it out so I decided I would buy another one just like it and simply leave it in the box until I needed it. (I did pull it out and put oil in it but never started it - didn't want gas in it...). This was probably 4 years ago so it has just been sitting in my shop.

A few weeks back, we lost power at home so I thought "well, we can sleep in the 5th wheel tonight and at least have Air Conditioning". I went to the shop and gassed up/powered up the Champion generator (started very easy). The 5th wheel has a 15,000 BTU Dometic AC unit but the generator is still within the specs to handle the bigger unit. I let the generator run for 5 to 10 minutes or so and plugged in the RV and flipped the switch for 120v. (It has a 30 amp RV plug on it). When I turned the thermostat on inside the 5th Wheel, it bogged down the generator so much (almost dying due to the load), that I quickly turned off the Thermostat as I was worried about hurting the AC unit. I tried it again a few minutes later with the same result so I have not messed with it since.

I have not contacted Champion yet. There is a "800" support line to call and I likely will but I thought I would ask some of you your thoughts. While the unit is "brand new" from a running point of view, it is now certainly out of any warranty period I am sure from Champion's point of view.

The AC unit is just fine when plugged into shore power.

Thoughts on this generator and why it would do this? In hind sight, I should have tried it out when I first brought it home but I didn't want carburetor issues even though I use Stabil in all my small engines.

Thanks in advance for your advice!

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